Can axolotls live with cardinal tetras?

Verdict

No. Axolotls and cardinal tetras should not share a tank. Axolotls are coldwater animals (60–66°F); cardinal tetras need 76–84°F. No temperature suits both.

Axolotl60–66°F · pH 6.5–8

Cardinal tetra76–84°F · pH 4.6–7

What to watch

Deal breakerAxolotls are coldwater animals (60–66°F); cardinal tetras need 76–84°F. No temperature suits both.
Deal breakerAt 10 inches an axolotl can swallow a 2-inch cardinal tetra whole.
Deal breakerFish nibble at axolotl gills, and axolotls swallow small fish. Keep axolotls on their own.

What works

pH 6.5–7 suits both.
They use different parts of the tank: axolotls the bottom, cardinal tetras the mid.

Water side by side

The ranges do not meet, so one of them would always be too warm or too cold.

The green band is the pH both tolerate.

Size to scale

Adult length in an aquarium. A fish can swallow anything that fits in its mouth, roughly a third to half its own length for predators.

Care at a glance

	Axolotl	Cardinal tetra
Temperature	60–66 °F	76–84 °F
pH	6.5–8	4.6–7
Adult size	10.0 in	2.0 in
Minimum tank	20 gal	20 gal
Temperament	Peaceful	Peaceful
Swims at	Bottom	Middle
Group	Alone or in pairs	Groups of 6+
Diet	Carnivore	Omnivore

Better tank mates for cardinal tetras

All cardinal tetra tank mates

Questions

Can axolotls live with cardinal tetras?

No. Axolotls and cardinal tetras should not share a tank. Axolotls are coldwater animals (60–66°F); cardinal tetras need 76–84°F. No temperature suits both.

What temperature suits both axolotls and cardinal tetras?

None. Axolotls need 60–66 °F and cardinal tetras need 76–84 °F, so the ranges do not meet.

What size tank do axolotls and cardinal tetras need together?

At least 20 gal, set by the axolotl. Add space for each extra fish.